1. Field of Invention
The present invention relates to a semiconductor package. More particularly, the present invention relates to a multi-chip semiconductor package.
2. Description of Related Art
In the semiconductor industry, the fabrication of integrated circuits is divided into three stages: the fabrication of wafers, the formation of integrated circuits, and the packaging of integrated circuits. The purpose of the packaging is to provide electrical connection between dies and a printed circuit board or other desired devices, as well as protection.
After the formation of integrated circuits, a wafer is cut into dies. In general, the dies have bonding pads thereon to provide die testing points, and to provide connection between the dies and other devices. In general, wires and bumps are provided to connect the dies and other devices.
FIG. 1 is a schematic, cross-sectional diagram of a conventional semiconductor package.
Referring to FIG. 1, a chip 100 is attached to a die pad 102, which is in the center region of a lead frame 104. Bonding pads 106 made of metal are mounted in one surface of the chip 100. The bonding pads 106 are used for coupling with other devices, and are typically made of aluminum. The surface of the chip 100 without bonding pads is fixed to the die pad 102 by an adhesive. After the chip 100 is fixed, each bonding pad 106 in the bonding pad surface of the chip 100 is coupled to each corresponding lead 110 by wires 108. The chip 100, wires 108, and a portion of the leads 110 are sealed in packaging material 112. The packaging material 112 fixes devices in their required positions and protects the chips 100 and the connection points of the chip 100 and the wires 108, and also prevents moisture from penetrating into the packaging. An exposed portion of the leads 110 is bent downward for coupling to a printed circuit board (not shown).
Increasing integration in integrated circuits creates increased requirements for packages. However, only one chip is packaged in a conventional package. Integration and performance are limited by only one chip in the conventional package so that the integration of devices and performance cannot be enhanced, and capital expenditure cannot be lowered. Therefore, it is important for the packaging industry to increase device integration and performance, and to further lower the capital expenditure.